Sealed electrical connector

ABSTRACT

A sealed electrical connector including a connector body containing a plurality of contacts and a cable boot mounted over a tapered projection on one end of the body. The projection is formed with channels aligned with the contact passages. The conductors of the cable lie in these channels. Keyways are formed in the projection which receive keys formed on the inner wall of the boot to restrain the boot from rotation relative to the connector body, and hence prevent twisting of the cable conductors. Integral sealing ribs are formed on the front and rear portions of the boot.

United States Patent [191 Anhalt et al. a

[ 1 SEALED ELECTRICAL CONNECTOR [75] Inventors: John W. Anhalt; David S.Goodman,

both of Orange; Edgar Burns, Los Angeles, all of Calif.

[73] Assignee: International Telephone and Telegraph Corporation, NewYork, NY.

[22] Filed: May 28, 1974 [21 Appl. No.: 473,586

{56] References Cited UNITED STATES PATENTS 2,033,973 3/1936 Clayton339/63 R 2,060,709 11/1936 Wertzheiser 339/63 R 2,255,763 9/1941Doughman 339/59 R 3.430.187 2/1969 Deman et al 339/103 R i l l 13,905,672

"*rm Sept. 16, 19'rs= Primary Examiner.loseph H. McGlynn AssistantExaminer-James W. Davie Attorney, Agent, or Firm-Thomas L. PetersonABSTRACT A sealed electrical connector including a connector bodycontaining a plurality of contacts and a Cable boot mounted over atapered projection on one end of the body. The projection is formed withchannels aligned with the Contact passages. The conductors of the cablelie in these channels. Keyways are formed in the projection whichreceive keys formed on the inner wall of the boot to restrain the bootfrom rotation relative to the connector body, and hence prevent twisting of the cable conductors. Integral sealing ribs are formed on thefront and rear portions of the boot.

12 Claims, 7 Drawing Figures PATENTEUSEPI 61975 905 6T SHIET 1 BF 2FIGJ.

SEALED ELECTRICAL CONNECTOR BACKGROUND OF THE INVENTION DESCRIPTION OFTHE PRIOR ART With the advent of legislation requiring the use of anti-skid control systems for brakes on trucks. the need has arisen forlow cost seated electrical connectors for making electrical connectionbetween the wheel speed sensor and the computer housing of the anti-skidcontrol system. Such connectors mustprevent the intrusion of moistureand other contaminates into the area of the connector containing theelectrical contacts in order that the electrical system of the anti-skidcontrol will not be adversely affected. Co-pending application ofGoodman et al., Ser. No. 381,267, filed July 20, 1973, entitled, LowCost Sealed Connector," discloses a connector assembly including matingplug and receptacle connector members which meet the required standardsfor anti-skid systems.

In these systems it is also necessary to connect a single connectormember into the housing of the control system computer. We have found itnecessary to include in the connector assembly an elastic boot whichprovides a seal between the main connector body con taining the contactsand the cable which carries the conductors from the wheel sensor to theconnector contacts. The use of rubber boots for electrical connectors,of course, is well known in the art. However, for this application theboot presents a problem in that a coupling nut is utilized on thehousing for securing the connector body and boot thereto. Rotation ofthe coupling nut causes rotation of the boot, which in turn may causethe conductors in the cable to twist. This may result in the electricalconnection between the conductors and the contacts being broken. Also,we have found that by utilizing a boot with a connector body in aconventional manner. a relatively large open cavity is provided at therear of the connector body where the boot engages the body. When theconnector is utilized on a vehicle which is operated at high altitudes,such as on mountain roads, the air trapped within this cavity willexpand due to decreased atmospheric pressure, which may result inseparation between the boot and the connector body, breaking the sealtherebetween.

This may permit the intrusion of moisture or other contaminates into theconnector and ultimately into the contact passages thereof. It is theobject of the present invention to overcome these problems. It is ofcourse understood that while the connector of the present invention hasbeen referred to as being suited for use in an anti-skid system forvehicles, it would be useful for any application wherein anenvironmentally sealed connection is required.

SUMMARY OF THE INVENTION According to the principal aspect of thepresent in' vention, there is provided a sealed electrical connectorincluding a connector body and a boot of elastic pliant material mountedon one end of the body. The body has a plurality of contact passagesextending therethrough and rearwardly extending projection which extendsinto an enlarged cavity in the end of the boot. A

The. insulatedconductors of thecable which extends into the boot lie inthese channels and are connected to, the contacts in the contactpassages. In addition, one or more longitudinally extending grooves areformed in the outer surface'of the projection. Longitudinally extendingribs extend inwardly from the wall of the cavity in the boot andslidably engage, in the grooves to restrain the boot from rotationrelative to the connector body. As a consequence, when a coupling nut isrotated about the boot to secure the connector and boot assembly into amounting member, the boot will be prevented from rotating relative tothe connector body, thereby preventing twisting of the conductorsconnected to the contacts in the body. Furthermore, the enlarged cavitynormally found between the end of the connector and the boot isessentially eliminated by the present invention due to the fact that theprojection on the rear of the connector body extends into the cavity inthe boot to substantially fill the. cavity, thereby minimizing anyentrapped air within the boot.

Other aspects and advantages of the invention will become more readilyappreciated by reference to the following detailed description whenconsidered in connection with the accompanying drawings in which likereference characters designate like parts throughout the various views,

BRIEF DESCRIPTION OF ril DR w Nos FIG. I is a partial verticalsectional-view through a mounting member containing the connector memberof the present invention; T

FIG Z is a partial vertical longitudinal sectional view of the connectorbody ;of the present invention;

FlG.-3 is an elevational view showing the rear of the connector body;

FIG. 4 is an elevational view showing the front of the connector body;

FIG. 5 is a vertical longitudinal sectional view of the boot employed inthe connector of the present invention;

FIG. 6 is an elevational view showing the front of the boot; and

FIG. 7 is an exploded perspective view of the connector body and theboot, with the boot being shown in partial section to illustrate thedetails of the interior structure thereof. w

DESCRIPTION OFTHE PREFERRED EMBODIMENT Referring now to FIG. I indetaiLthere is illustrated a cover plate I0 for a housing, not shown,containing the computer of a anti-skid control system. The housingcontains a printed circuit board 12 on which there is mounted aheader.l4 which has a plurality of out wardly extending pin contacts 16on the exposed end thereof. In the example shown, three of such contactsare employed, only one beingvisible in FIG. I. It will be appreciatedhowever that a larger or fewer number of contacts may be utilized.Typically, three or four contacts are used. An externally threadedcylindrical boss 18 is formed on the plate 10 coaxial with the header[4. A cylindrical bore 20 extends through the boss. The end of theheader extends into one end of the bore. The electrical connector memberof the present invention, generally designated 22, extends into theother end of the bore. The connector is retained in the bore by means ofa coupling nut 24. This nut is formed with a radially inwardly extendingannular flange 26 which engages a thrust washer 27 abutting a sealingbushing 28 that engages a rearwardly facing shoulder 30 on theconnector. Threading of the nut 24 on the boss 18 urges the sealingbushing 28 into engagement with end of the boss, and urges the connectorinto the bore toward the header 14.

Referring now to FIGS. 2-7 of the drawings. the connector member 22comprises an elongaged generally cylindrical insulator body 32 and acable boot 34. Except for the contacts mounted in the body, the body andthe boot each consist of a unitary mass of molded elastic pliantmaterial which is chemically resistant to hostile environments andvarying temperature conditions. Any thermoplastic elastomer', such aspolyurethane polyether, for example. could be utilized as the materialfor the connector parts. it will be appreciated. however, that otherelastomers could be utilized if they possess the requiredcharacteristics of resiliency, flexibility, and softness to produceeffective seals when configured in accordance with the presentinvention.

The diameter of the body 32 is slightly less than the diameter of thebore 20 to allow the body to be slidably mounted within the bore. Thelower portion of the body is cut out to provide a downwardly facing flatsurface 36 which extends from a forwardly facing shoulder 38 to thefront face 40 of the body. The surface 36 cooperates with a flat raisedsection 42 on the bottom of the bore 20 in the plate 10 to providepolarization of the connector with respect to the header l4 and alsononrotatably mount the connector in the plate. The raised section 42also forms a shoulder 44 which provides a stop engage-able by theshoulder 38 on the body 32 thereby limiting movement of the connector 22into the bore 20.

The connector body 32 is provided with a plurality of axially alignedlongitudinally extending contact passages 50, which extend from thefront face 40 of the body to the rear face 52 thereofThree of suchpassages are shown in FIGS. 3 and 4, corresponding in number to the pincontacts 16 in the header 14. A socket contact 54 is positioned in eachpassage which is mateable witha pin contact 16 when the connector member22 is fully mounted within the bore 20 in plate [0. Each contactterminates an insulated wire 56 of a cable 58 which extends through apassageway 60 in the boot 34. In FIG. 2. the contact is shown as beingof the closed barrel type, the barrel being crimped onto the wire.Otlier termination techniques may obviously be utilized.

Means are integrally formed on the connector body 32 for retaining thecontacts 54 therein. Such means comprises an annular flange 60 whichextends radially inwardly from the wall of each contact passage 50. Theflange is sufficiently resilient and pliant to allow the contact to passtherethrough when it is inserted into the rear of the contact passage.Each contact is formed with an annular recess 62. The depth of therecess and the radial dimension of each flange 60 are such that theflange will have a snug fit in the recess to hold the contact againstappreciable longitudinal movement rel ative to the connector body.

A central relatively rigid projection 64 extends from the rear face 52of the connector body 32. This projection is tapered to provide afrustoconical outer surface 66. [t is noted that the contact passages 50are circumferentially spaced about the body 32 adjacent to the outerperiphery of the body. A plurality of channels 68 are formed in theouter surface of the projection 64. Each channel is aligned with arespective contact passage 50. Each channel 68 is sufficiently deep toreceive an insulated wire 56 therein, without the wire extending abovethe outer surface 66 of the projection. It is noted that the bottoms ofthe channels 68 are curved to accommodate the insulated wires.

A plurality of grooves or keyways 70 are also formed in the outersurface of the projection 64. These grooves are disposed alternatelywith respect to the channels 68. The grooves have a rectangular crosssection. The bottom of each groove is parallel to the longitudinal axisof the body 32. The channels 68 and grooves 70 extend to the end of theprojection 64.

The passageway 60 in the boot 34 terminates in an enlarged cavity 72which has a frustoconical wall complementa'ry to the frustoconical outersurface 66 of the projection 64. A plurality of longitudinally extendingribs or keys 74 extend inwardly from the wall of the cavity 72. Theseribs are aligned with the groove 70 and have a configurationcomplementary to the grooves so that when theboot 34 is mounted over theprojection 64 on the body 32 the ribs 74 will be slidably engaged withinthe grooves. The depth of the grooves 70 and the radial distance of theribs 74 are sufficiently great to prevent relative rotation between thecable boot and the body 32 when the rotational force imparted by thecoupling nut 24 is imposed upon the boot in the assembly illustrated inFIG. 1. Thus, by this arrangement the insulated wires 56 will not betwisted when the coupling nut is rotated to fixedly mount the connector22 in the plate 10. It is further noted that the projection 64 on thebody 32 substantially completely fills the cavity 72 in the boot 34,thus minimizing any entrapped air within the boot. Furthermore, themating frustoconical surfaces 66 and 72 on the body 32 and the boot 34,respectively, sealihgly engage each other when the coupling nut 24 istightened upon the boss 18, and also the forward edge 76 of the bootengages the rear face 52 of the body 32, thereby providing a seal forthe contacts. This latter seal is in effect a secondary seal for thecontacts. The primary seal for the contacts is provided by means of aplurality of integral longitudinally spaced annular sealing ribs 78formed on the forward portion of the boot 34 which surrounds theprojection 64. These ribs are deformable and are dimensioned so as tohave an interference fit with the wall of the bore 20, thereby producingan intimate mechanical contact and labyrinth seal between the boot andthe wall of the bore 20. It is further noted that the tapered projection64 junctions as a wedge urging the ribs 78 outwardly into tight sealingengagement with the wall of the bore 20 when the forward end of the bootis forced into the bore by the coupling nut.

A plurality of annular longitudinally spaced integral ribs 80 are formedon the wall of the passage 60 adjacent to the rear portion of the boot34. These ribs have an interference fit with the insulation on the cable58, thereby providing a rear seal between the boot and the cable. Thus.the total assembly is completely sealed when the coupling nut istightened on the boss 18.

To assembly the connector parts. and then mount the connector in theplate H). the receptacle contacts 54 are crimped to the exposed ends ofthe wires 56. The boot 34 is then forced over the cable 58 leaving thecontacts and the ends of the Wires 56 exposed. The contacts are thenforced into the contact passages 50 in the connector body 32 by pressingthem into the passages from the rear of the body. The conductors willthen lie in the channel 68. The forward end of the boot 34 is thenpushed over the projection 64 on the body 32. The connector member thusformed is then inserted into the bore 20 with the flat surface 36aligned with the flat raised section 42 of the bore. thereby properlypolarizing the connector. The connector member is pushed into the boreuntil the shoulder 38 thereon engages the shoulder 44 in the bore. Withthe connector so mounted. the pin contacts 16 on the header will beslidably engaged into the receptacle contacts 54 in the connector. Nextthe sealing bushing 28. thrust washer 27. and coupling nut 24 aremounted over the other end ofthe cable and the nut is tightened on theboss [8 which exerts a forward axially extending force upon therearwardly facing shoulder 30 on the boot 34 thereby tightly retainingthe connector in the bore. This mounting operation also forces thefrustoconical wall of the cavity 72 into sealing engagement with theouter surface 66 of the projection 64. and the front edge 76 of the bootinto sealing engagement with the rear face 52 of the body 32. Inaddition. the forcing of the boot into the bore causes the ribs 78 toscaling engage the wall ofthc bore 20. Since the sealing ribs 78surround the projection 64, the projection provides a relatively rigidsupport for the ribs. assuring that the ribs remain in interference litwith the wall of the bore 20. Thus. a completely sealed assembly isprovided. with a minimum of entrapped air within the boot 34. andrelative rotation between the cable and the connector body 32 isprevented during rotation ofthe coupling nut due to the inter-engagementbetween the ribs 74 and the grooves 70 on the boot and connector body.respectnely.

What is claimed is;

I. An electrical connector member comprising:

an elongated insulator body having a front face and rear face;

a plurality ofcontact passages in said body extending from said frontface to said rear face. said passages being spaced from the outerperiphery of said body;

a projection on said body extending rcarwardly from said rear face. saidprojection having a circular cross'section less than the cross-sectionof said body defining on said rear face a rearwardly facing annularsurface;

a plurality of longitudinally extending channels in the outer surface ofsaid projection each aligned with a respective one of said passages;

at least one longitudinally extending groove in the outer surface ofsaid projection;

a boot of elastic pliant material at the rear of said body ha\ing apassageway extending thercthrough terminating in an enlarged can it atone end receiving said projection. the wall of said cavity engaging theouter surface of said projection. said boot hm mg a forward edgeengaging said annular surface; and

longitudinally extending rib extending inwardly from said all of saidcavity. said rib slid-ably en- Ill gaging with said groove to restrainsaid boot from rotation to said body.

2. An electrical connector as set forth in claim 1 wherein there areprovided:

a plurality of said grooves circumferentially spaced about the outersurface of said projection and a plurality of said ribs aligned andslidably engaged with said grooves.

3. An electrical connector as set forth in claim 2 wherein:

said grooves are alternately disposed with respect to said channels.

4. An electrical connector as set forth in claim 1 wherein:

said projection tapers rearwardly to define a frustoconical outersurface; and

the wall of said cavity in said boot has a configuration complementaryto that of said surface.

5. An electrical connector as set forth in claim 1 including:

a plurality of integral longitudinally spaced. continuous annularsealing ribs formed on the outer surface of said boot adjacent to theforward end thereof surrounding said projection.

6. An electrical connector as set forth in claim 1 in cluding:

an electrical Contact in each of said passages;

a cable mounted in said passageway in said boot. said cable having aplurality of insulated conductors therein extending forwardly into saidcavity; and

the end portion of each said insulated conductor lying in a respectiveone of said channels and being electrically connected to the contact inthe passage aligned with said channel.

7. An electrical connector as set forth in claim 6 including:

integral retention means in each said passage engaging with the contacttherein to restrict said contact against longitudinal movement in saidpassage.

8. An electrical connector as set forth in claim 6 including:

a plurality of integral longitudinally spaced annular sealing ribsformed on the wall of said passageway adjacent the rear of said boot.said ribs sealingly engaging the outer surface of said cable.

9. An electrical connector as set forth in claim 1 wherein:

the wall of said cavity sealingly engages the outer surface of saidprojection except at said channels and groove.

10. An electrical connector member as set forth in claim 1 incombination with a mounting member including an externally threaded bosshaving a bore extending thcrethrough wherein:

said connector member is mounted in said bore;

cooperating surface means are formed in said bore and on the outersurface of said body restraining said body against rotation in saidbore:

a rearwardly facing shoulder on said boot; and a coupling nut threadedon said boss having an inwardly extending rear flange which acts uponsaid shouldcr to force said boot axially into said bore against saidbody upon rotation of said nut.

11. An electrical connector as set forth in claim 10 including.

a plurality of integral longitudinally spaced annular scaling ribsformed on the outer surface of said boot forward of said shouldersealingly engaging the wall of said bore.

12. An electrical connector member comprising: an elongaged insulatorbody having a front face and a rear face;

a plurality of contact passages in said body extending from said frontface to said rear face and disposed adjacent to but spaced from theouter periphery of said body;

central projection on said body extending rearwardly from said rearface, said projection tapering rearwardly to define a frustoconicalouter surface. said projection having a cross-section less than that ofsaid body defining on said rear face a rearwardly facing annularsurface;

a plurality of longitudinally extending channels in the outer surface ofsaid projection each aligned with a respective one of said passages;

a plurality of longitudinally extending keyways in the a plurality oflongitudinally extending keys extending inwardly from said wall of saidcavity and aligned with said grooves, said keys slidably engaging withsaid keyways to restrict said boot from rotation rel ative to said body.

1. An electrical connector member comprising: an elongated insulatorbody having a front face and rear face; a plurality of contact passagesin said body extending from said front face to said rear face, saidpassages being spaced from the outer periphery of said body; aprojection on said body extending rearwardly from said rear face, saidprojection having a circular cross-section less than the cross-sectionof said body defining on said rear face a rearwardly facing annularsurface; a plurality of longitudinally extending channels in the outersurface of said projection each aligned with a respective one of saidpassages; at least one longitudinally extending groove in the outersurface of said projection; a boot of elastic pliant material at therear of said body having a passageway extending therethrough terminatingin an enlarged cavity at one end receiving said projection, the wall ofsaid cavity engaging the outer surface of said projection, said boothaving a forward edge engaging said annular surface; and alongitudinally extending rib extending inwardly from said wall of saidcavity, said rib slidably engaging with said groove to restrain saidboot from rotation to said body.
 2. An electrical connector as set forthin claim 1 wherein there are provided: a plurality of said groovescircumferentially spaced about the outer surface of said projection anda plurality of said ribs aligned and slidably engaged with said grooves.3. An electrical connector as set forth in claim 2 wherein: said groovesare alternately disposed with respect to said channels.
 4. An electricalconnector as set forth in claim 1 wherein: said projection tapersrearwardly to define a frustoconical outer surface; and the wall of saidcavity in said boot has a configuration complementary to that of saidsurface.
 5. An electrical connector as set forth in claim 1 including: aplurality of integral longitudinally spaced, continuous annular sealingribs formed on the outer surface of said boot adjacent to the forwardend thereof surrounding said projection.
 6. An electrical connector asset forth in claim 1 including: an electrical contact in each of saidpassages; a cable mounted in said passageway in said boot, said cablehaving a plurality of insulated conductors therein extending forwardlyinto said cavity; and the end portion of each said insulated conductorlying in a respective one of said channels and being electricallyconnected to the contact in the passage aligned with said channel.
 7. Anelectrical connector as set forth in claim 6 including: integralretention means in each said passage engaging with the contact thereinto restrict said contact against longitudinal movement in said passage.8. An electrical connector as set forth in clAim 6 including: aplurality of integral longitudinally spaced annular sealing ribs formedon the wall of said passageway adjacent the rear of said boot, said ribssealingly engaging the outer surface of said cable.
 9. An electricalconnector as set forth in claim 1 wherein: the wall of said cavitysealingly engages the outer surface of said projection except at saidchannels and groove.
 10. An electrical connector member as set forth inclaim 1 in combination with a mounting member including an externallythreaded boss having a bore extending therethrough wherein: saidconnector member is mounted in said bore; cooperating surface means areformed in said bore and on the outer surface of said body restrainingsaid body against rotation in said bore; a rearwardly facing shoulder onsaid boot; and a coupling nut threaded on said boss having an inwardlyextending rear flange which acts upon said shoulder to force said bootaxially into said bore against said body upon rotation of said nut. 11.An electrical connector as set forth in claim 10 including: a pluralityof integral longitudinally spaced annular sealing ribs formed on theouter surface of said boot forward of said shoulder sealingly engagingthe wall of said bore.
 12. An electrical connector member comprising: anelongaged insulator body having a front face and a rear face; aplurality of contact passages in said body extending from said frontface to said rear face and disposed adjacent to but spaced from theouter periphery of said body; a central projection on said bodyextending rearwardly from said rear face, said projection taperingrearwardly to define a frustoconical outer surface, said projectionhaving a cross-section less than that of said body defining on said rearface a rearwardly facing annular surface; a plurality of longitudinallyextending channels in the outer surface of said projection each alignedwith a respective one of said passages; a plurality of longitudinallyextending keyways in the outer surface of said projection disposedalternately between said channels; a boot of elastic pliant material atthe rear of said body having a passageway extending therethroughterminating in an enlarged cavity at one end receiving said projection,the wall of said cavity having a frustoconical configurationcomplementary to the outer surface of said projection whereby said wallsealingly engages the outer surface of said projection, said boot havinga forward edge engaging said annular surface; and a plurality oflongitudinally extending keys extending inwardly from said wall of saidcavity and aligned with said grooves, said keys slidably engaging withsaid keyways to restrict said boot from rotation relative to said body.